When you turn down or up the volume on devices with either a wheel or button, what actually happens that allows it to sound quieter or louder?
In: Technology
So what it is, is inside the switch is a device that amplifies a signal, or a signal inverse of that signal, and so the more power you give to that amplifier, the higher the peak of that signal (which is going to be volume)
It’s a wheel that literally changes the resistance of the circuit. There are rheostats and potentiometers. Pots generally control voltage, rheostats control current. There is a distinction, and it mostly matters when you’re using AC or DC. Basically, you’re increasing, or decreasing resistance.
A long time ago I took a radio volume knob off and I saw that it was a cylinder with copper wire wrapped around it in a tight coil all the way down. As you turned the knob, the cylinder slid further into or out of the hole, changing the place along the length of the wire where it made contact with the rest of the circuit. The longer the amount of wire the electricity had to travel through, the more resistance, and the lower the volume. I’m sure modern ones are a lot more sophisticated, but the principle is the same.
a capacitor with controlled resistance makes the sound louder or quieter. if the volume is low the resistance is high causing the sound to be quieter
Two different methods.
Analog devices are often continuous and involve the moving of a variable capacitor or resistor to change the electric makeup going to the speaker.
In a digital device nothing changes really, the knob is a user interface that tells a circuit to apply more or less voltage. However b/c it’s digital (all 1s and 0s) you never get continuous band control. Think if you’ve ever had a problem with a digital speaker that is too loud on one step and too quiet on the lower step
U/toxiclay had half the story: the other half are the buttons which are just momentary switches that tell the microcontroller to lower the volume by software. Like in your phone, you can program the input to be contextual, as well, so if you find your volume button it will bring up the power optima for sitting down/resetting the phone, or take a picture if you’re in the camera app.
The speaker holes get bigger or smaller depending on the buttons or direction of knob spinning and the phase of the moon
I’ma tell you what I know, because I made quite a few of these circuits in the past year, someone more knowledgeable should critique me.
Your knob is a potentiometer, which is essentially a variable resistor. By turning the knob, you will either increase or decrease the resistance within the circuit. Due to ohm’s law, this will also affect your current and voltage.
By decreasing the resistance (turning up the volume) you are increasing the voltage and current. This increased voltage will go and power the electromagnetic vibrations within your speaker.
My question is, how does that speaker actually being “louder” happen? Is it just from the speaker operating at a higher or lower frequency? If someone could explain what’s happening within the speaker itself that makes us interpret the sound as louder I’d appreciate it.
Wildly simplified:
Imagine a strip or a rod, which has some electrical resistance.
One wire is connected to the end, the other slides up and down on the strip.
When you slide far away, the resistance between the 2 wires is bigger, and gets smaller as you slide the other way.
(Potentiometers are a bit more complex than this, but this is the overall simple concept of it)
There are various ways to do it. One is a potentiometer (if the knob has a hard low stop and hard high stop it may be like this), or it could use essentially micro switches to send pulses that the device uses to count up or down. There are probably other ways to do it as well.
Latest Answers